Study on Free Amino Acid and Short Peptide Fertilizer Production by Solid State Fermented Castor Bean Meal

Using microbial fermentation to increase the content of free amino acids and short peptides in the organic fertilizer for castor bean meal can effectively promote plant growth and improve fruit quality.Using free amino acid and short peptide content as an indicator,through single factor and response surface optimization experiments,the process parameters(moisture content,fermentation time and inoculum quantity)of castor meal solid-state fermentation were optimized.The best process parameters for the solid-state fermentation were:the moisture content 62%,the fermentation time 20 d,and the inoculum quantity 0.23%.The moisture content had the greatest impact on the conversion rate of free amino acids and short peptides,and the protein conversion rate reached 65.6%.The scale-up experiment under the optimal conditions showed that the solid-state fermentation using the inoculum had a significant beneficial effect compared with other fermentation methods.The fermentation of castor cake fertilizer provides a theoretical and practical basis for production feasibility,and has important guiding significance for the effective utilization of castor bean meal.

The role of aromatic residues in controlling the supramolecular chirality of short amphiphilic peptides

Although the relationship between molecular and supramolecular chirality remains elusive,the existing results have demonstrated the vital role of hydrophilic motifs in controlling the supramolecular handedness of peptide nanofibrils compared with hydrophobic ones.However,unlike conventional hydrophobic residues,we speculate that aromatic hydrophobic residues are mostly likely to play a unique role in regulating the supramolecular handedness because theπ–πstacking interactions of their side chains are directional like hydrogen bonding and can direct high levels of self-assembly due to the geometric confining of aromatic rings.To confirm this hypothesis,we here design a series of amphiphilic short peptides,with their hydrophobic motifs being composed of aromatic residues.Their short lengths not only favor their structural stability,synthesis,and sequence variation but also enable us to readily link their molecular and supramolecular structures.Through the combination of experiments and theoretical simulations,we demonstrate that the peptides containing L-form aromatic residues form left-handed nanofibrils while those containing D-form aromatic residues assemble into right-handed ones,irrespective of the chirality of their C-terminal hydrophilic residue.Theoretical calculations revealed that the stacking of aromatic side chains betweenβ-strands directed the twisting direction of theβ-sheets formed,with L-and D-form phenylalanine side chains stacking in a clockwise and anti-clockwise way,and more ordered and stronger aromatic stacking for homochiral peptides facilitated the formation of nanofibrils with a marked tubular feature.This study has bridged the knowledge gap in our understanding of how aromatic residues affect the supramolecular chirality of short peptides.

An iASPP-derived short peptide restores p53-mediated cell death in cancers with wild-type p53

Background:Inhibitor of apoptosis-stimulating protein of p53(iASPP)is an evolutionarily conserved p53 inhibitor.Mechanistically,iASPP can accelerate tumorigenesis by inhibiting the transactivation function of p53.Targeting the interaction between iASPP and p53 may be a potential therapy for restoring the activity of p53 in tumors.Methods:We constructed an iASPP-derived peptide,called A8,that was derived from the C-terminus of iASPP.Here,we transfected A8 into two wildtype(WT)p53 cell lines,U2OS and A549,and then determined the number of apoptotic cells.The mechanism by which A8 affected apoptosis was further examined by immunoprecipitation(IP),Dual-Luciferase reporter assays,and chromatin IP assays.Real-time polymerase chain reaction and western blots were also used to examine the expression levels of apoptosis-related factors.Results:Our data demonstrate that A8 can increase apoptosis rates in WT p53 cell lines.Functional analysis suggested that A8 restored the transcriptional function and DNA binding activities of p53 toward the Bax and PUMA gene promoters.Moreover,A8 reduced cell proliferation and inhibited tumor growth in xenograft nude mice.Conclusions:These data provide a new approach for restoring the tumor suppressor function of p53 in cancer cells that express WT p53 and therefore may serve as a novel cancer treatment strategy.

Selection of Immunogenic Peptide Mimics of Male Worm Origin of Schistosoma Japonicum using Phage Display Peptide Library

To select the immunogenic short peptide mimics of male worm origin of Schistosoma japonicum (Sj) and to explore their protection effect against schistosomiasis in mice, the random phage display peptide library of 12-mer was screened with IgG to soluble male worm antigen of Sj, and the specific positive clones selected through three rounds of screenings were detected by Dot-ELISA, and then injected subcutaneously into mice for vaccination and protection assessment against Sj. It was found that 18 randomly picked phage displayed clones all showed definite antigenicity with various intensities. The pooled phages displayed clones could induce production of specific antibodies and cause 31.72% of worm reduction rate and 51.54% of egg reduction rate in mice, revealing a significant difference (P<0.001) in comparison with those of the controls. It concludes that the short peptide mimics of male worm origin of Sj obtained by affinity screening phage display peptide library can elicit partial protection against this pathogen.

Denting Nanospheres with a Short Peptide

Dented n anospheres show promisi ng potential in drug delivery,nano motors,etc.However,it is still challe nging to prepare them by homopolymer self-assembly because of the strict structural requirements of the homopolymer.Herein,we propose a strategy for preparing dented nano spheres from homopolymers by co-assembly with a short peptide.They were co-assembled from poly(2-hydroxy-3-((4-(ethoxycarbonyl)phenyl)amino)propyl methacrylate)(PHBzoMA59)and(S)-2-((S)-2-((((9H-fluoren-9-yl)methoxy)carbonyl)amino)-3-phenylpro-panamido)-3-phenyIpropanoic acid(Fmoc-FF-OH).PHBzoMA homopolymers can only self-assemble into nanospheres without dent,and the addition of a short peptide in troduced hydroge n bondi ng and complementary π-π stacki ng interactions led to the final dented nano sphere morphology.The weight fracti ons of the short peptide can be adjusted to regulate the final morphology.It was con firmed that the radius of curvature of the dent on the surface was related to the organic bubble inside the protospheres prepared at critical aggregation concentration(CAC).The orga nic bubble can be adjusted by altering the kind of orga nic solve nt and solution pH,which allowed control over the dented nano sphere dimension.The use of differe nt orga nic solve nts with various polarities allows adjustment of the interfacial tension,and hence the denting degree.This degree can also be controlled by manipulating the solution pH to(de)protonate the short peptide and homopolymer.Furthermore,the versatility of this method was highlighted by using a differe nt homopolymer and the applicability of the resulting den ted nanospheres was demonstrated by decoration with gold nanoparticles.Overall,this study provided important insights and a new simple strategy to prepare den ted n anospheres in a con trolled fashion.